In today's world, the task of detecting concealed bombs and weapons is becoming more and more important. The higher the resolution of the radio image, the higher the probability of concealed dangerous object detection and the lower the false alarm rate. However, presently available systems do not provide a mobile yet economical solution to detect dangerous objects by reconstructing discernible images of scanning objects.
Most of the current systems for detecting explosive devices and weapons are based on electromagnetic field technology. Such systems require individual objects to pass through a fixed passageway. When metallic objects pass through the passageway, a warning signal is activated indicating a change in magnetic flux. This type of system simply detects metal objects making no determination relative to the amount of metal present. Keys, jewelry, watches, and metal-framed eyeglasses may all trigger such a system.
Another type of detection system generates a microwave image of an object in addition to optical image information. While microwave imaging can provide additional information on concealed objects when used in conjunction with an optical image, microwave imaging still lacks the precision necessary for accurate weapon recognition.